Automatic headlamp control

• US 7,004,606 B2
• Filed: 04/23/2003
• Issued: 02/28/2006
• Est. Priority Date: 04/23/2002
• Status: Expired due to Fees

• Current Assignee: Donnelly Corporation (Magna International Incorporated)
• Original Assignee: Donnelly Corporation (Magna International Incorporated)
• Inventors: Schofield, Kenneth
• Primary Examiner(s): O'Shea, Sandra
• Assistant Examiner(s): Lee, Guiyoung
• Application Number:
  US10/421,281
• Publication Number:
  US 20030227777A1
• Time in Patent Office: 1,042 Days
• Field of Search: 362/464, 362/465, 362/466, 362/467, 362/460, 250/205, 250/221, 250/216, 250/214.D, 315/82, 382/104
• US Class Current: 362/460
• CPC Class Codes: B60Q 1/1423 Automatic dimming circuits, i.e. switching between high beam and low beam due to change of ambient light or light level in road traffic
• CPC Class Codes: B60Q 2300/054 Variable non-standard intensity, i.e. emission of various beam intensities different from standard intensities, e.g. continuous or stepped transitions of intensity
• CPC Class Codes: B60Q 2300/146 Abnormalities, e.g. fail-safe
• CPC Class Codes: B60Q 2300/312 Adverse weather
• CPC Class Codes: B60Q 2300/41 preceding vehicle
• CPC Class Codes: B60Q 2300/42 oncoming vehicle
• CPC Class Codes: G06V 20/584 of vehicle lights or traffic lights

Abstract

An automatic headlamp control system includes an image sensor, such as an imaging array sensor, and a control. The image sensor is operable to capture an image of a scene forwardly of the vehicle and the control is operable to process the image to determine if any light sources in the captured image are indicative of headlamps of oncoming vehicles or taillights of leading vehicles. The control may adjust the state of the headlamps between a high beam state and a lower beam state in response to such processing of the captured image. The control may be operable to distinguish a reflection of the controlled vehicle'"'"'s headlamps from the taillights of a leading vehicle, headlamps of an oncoming vehicle, other light sources, and/or reflections from other light sources via recognition of a signature, code or pattern superimposed on the light output of the headlamps of the controlled vehicle.

Claims

1. An automatic headlamp control system for controlling the beam illumination state of at least one headlamp of a vehicle, said automatic headlamp control system comprising:

at least one headlamp of the controlled vehicle, said at least one headlamp being operable to at least occasionally emit a modulated light output, said modulated light output having at least one of a signature, a code and a pattern superimposed thereon;

an image sensor having a field of view forwardly of the vehicle, said image sensor being operable to capture an image of a scene forwardly of the vehicle;

a control operable to process said image to identify at least one light source within the field of view of said image sensor and to determine if the detected at least one light source is indicative of at least one headlamp of an approaching vehicle or at least one taillight of a leading vehicle, said control being at least occasionally operable to process said image to distinguish a reflection of said modulated light output as captured in said image via recognition of said at least one of a signature, a code and a pattern superimposed on said modulated light output, said control being operable to adjust the beam illumination state of said at least one headlamp between a high beam state and a lower beam state in response to said image processing.

2. The automatic headlamp control system of claim 1, wherein said control is operable to distinguish said reflection of said modulated light output from at least one of a taillight of a leading vehicle, a headlamp of an approaching vehicle, other light sources remote from the controlled vehicle and reflections from other light sources.

3. The automatic headlamp control system of claim 1, wherein said control is operable to distinguish said reflection of said modulated light output in response to said control determining that a detected light source in said image may be indicative of a headlamp of an approaching vehicle or a taillight of a leading vehicle.

4. The automatic headlamp control system of claim 1, wherein said at least one headlamp is operable to emit said modulated light output having at least one of a signature, a code and a pattern superimposed thereon in response to said control determining that a detected light source in said image may be indicative of a headlamp of an approaching vehicle or a taillight of a leading vehicle.

5. The automatic headlamp control system of claim 4, wherein said control is operable to distinguish said reflection of said modulated light output in said image via recognition of said at least one of a signature, a code and a pattern superimposed on said modulated light output in response to said control determining that the detected light source in said image may be indicative of a headlamp of an approaching vehicle or a taillight of a leading vehicle.

6. The automatic headlamp control system of claim 1, wherein said at least one headlamp is operable emit a modulated light output having a signature superimposed thereon and said control is operable to distinguish said reflection of said modulated light output via recognition of the signature superimposed on said modulated light output.

7. The automatic headlamp control system of claim 1, wherein said at least one headlamp is operable to emit a modulated light output having a code superimposed thereon and said control is operable to distinguish said reflection of said modulated light output via recognition of the code superimposed on said modulated light output.

8. The automatic headlamp control system of claim 1, wherein said at least one headlamp is operable to emit a modulated light output having a pattern superimposed thereon and said control is operable to distinguish said reflection of said modulated light output via recognition of the pattern superimposed on said modulated light output.

9. The automatic headlamp control system of claim 1, wherein said control is operable to compare images captured when said modulated light output is emitted to images captured when a non-modulated light output is emitted that does not have a signature, code or pattern superimposed thereon to determine if a detected light source is a reflection of said light output of said at least one headlamp.

10. The automatic headlamp control system of claim 1, wherein said control is operable to identify precipitation via recognition of said at least one of a signature, a code or a pattern superimposed on said modulated light output.

11. The automatic headlamp control system of claim 1, wherein said control is operable to provide a warm-up current to a high beam lighting element or a lower beam lighting element prior to the adjustment of the beam illumination state of said at least one headlamp to the high beam state or the lower beam state, respectively.

12. The automatic headlamp control system of claim 11, wherein said control is operable to provide said warm-up current to the high beam lighting element in response to a determination that a condition surrounding the vehicle is appropriate for high beam illumination.

13. The automatic headlamp control system of claim 1, wherein said control is operable to provide an adjustment between the high beam state and the lower beam state via ramping up energization of one of a high beam lighting element of said at least one headlamp and a lower beam lighting element of said at least one headlamp while ramping down energization of the other of the high beam lighting element and the lower beam lighting element.

14. The automatic headlamp control system of claim 1, wherein said at least one headlamp comprises a pair of headlamps.

15. The automatic headlamp control system of claim 14, wherein said control is operable to independently adjust the beam illumination state of each of said headlamps of the controlled vehicle in response to said image processing.

16. The automatic headlamp control system of claim 1, wherein said control is operable to adjust the beam illumination state of said at least one headlamp from the high beam state to the lower beam state in response to a detection of a light source in said image which may be indicative of at least one of a headlamp of an approaching vehicle and a taillight of a leading vehicle and nonrecognition of said at least one of a signature, a code and a pattern superimposed on said modulated light output.

17. The automatic headlamp control system of claim 1, wherein said control is operable to maintain the beam illumination state of said at least one headlamp in the high beam state in response to a detection of a light source in said image which may be indicative of at least one of a headlamp of an approaching vehicle and a taillight of a leading vehicle and recognition of said at least one of a signature, a code and a pattern superimposed on said modulated light output being associated with the detected light source.

18. An automatic headlamp control system for controlling the beam illumination state of a pair of headlamps of a vehicle, said automatic headlamp control system comprising:

an image sensor having a field of view forwardly of the vehicle, said image sensor being operable to capture an image of a scene forwardly of the vehicle and

a control operable to process said image to determine if a light source within the scene is indicative of a headlamp of an approaching vehicle or a taillight of a leading vehicle, said control being operable to independently adjust the beam illumination state of each of the headlamps of the controlled vehicle between a high beam state and a lower beam state in response to said image processing, said control being occasionally operable to independently adjust one of thc headlamps to the lower beam state, and the other of the headlamps to the high beam state in response to said image processing, said control being operable to adjust one of the headlamps to lower beam state in response to a determination that a detected light source in the captured image is indicative of a headlamp of an approaching vehicle or a taillight of a leading vehicle, said control being operable to adjust the other of the headlamps to a high beam state in response to a determination, that a detected light source in the captured image is a reflection of at least one of the headlamps of the controlled vehicle, wherein said control is operable to determine that the detected light source is a reflection of at least one of the headlamps of the controlled vehicle via recognition of at least one a signature, a code and a pattern superimposed on the light output of the headlamps of the controlled vehicle.

19. The automatic headlamp control system of claim 18, wherein said control is operable to independently adjust the beam illumination state of the headlamps in response to at least one of an orientation of the steering wheel of the controlled vehicle and an orientation of the front wheels of the controlled vehicle.

20. The automatic headlamp control system of claim 18, wherein said control is operable to independently adjust the beam illumination state of the headlamps in response to a location of the detected light source in the captured image.